On-Chip Quantum Randomness Amplification

Lang Li; Yutian Wu; Giulio Chiribella; Ravishankar Ramanathan

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arXiv · 2606.12173

On-Chip Quantum Randomness Amplification

Lang Li·Yutian Wu·Giulio Chiribella·Ravishankar Ramanathan

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Abstract

Randomness amplification, the task of extracting uniform private bits from biased seeds that may be partly known by a malicious third party, is of central importance in cryptography. The highest security in this task is provided by a class of quantum protocols known as device-independent, which however are challenging to integrate into scalable devices. Semi-device-independent (SDI) protocols are a promising alternative that guarantees security under few natural assumptions, such as bounds on the amount of energy used by the devices. Here, we provide the first demonstration of SDI randomness amplification on an integrated silicon photonic chip, achieving a throughput rate of 20 Mbps suitable for practical applications. This rate is achieved through a novel technique for SDI entropy certification, which delivers strictly tighter von Neumann entropy bounds compared to existing methods and remains valid even if the preparation and measurement devices share quantum correlations. Overall, the methods developed in this work enable the integration of SDI technology into portable telecom devices, opening up a new generation of quantum cryptographic hardware.

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Lang Li, Yutian Wu, Giulio Chiribella, Ravishankar Ramanathan. 2026-06-10. On-Chip Quantum Randomness Amplification. https://arxiv.org/abs/2606.12173

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